Emplacement mechanisms and the role of mass wasting in the Gulf of Corinth

该暂停奖提案旨在更好地了解大规模破坏矿床的就位机制，包括宏观和微观分辨率，这些矿床是在IODP第381次考察“科林斯活动裂谷开发”的M0079 A孔岩心中发现的。该项目将有助于实现考察的主要目标之一，即了解活动裂谷的地表过程以及构造和气候对沉积物通量的相对影响。它还将有助于实现第二个目标，即提高我们对科林斯裂谷地区地震、山崩和海啸危险的认识。为了实现这些目标，它是至关重要的，以了解以前的质量故障事件在整个裂谷盆地的演变同裂谷沉积物填充和滑坡频率分析区域地质灾害。此外，这项研究将有助于评估水下物质流对海底基础设施（如电缆、管道、海底设施）的潜在风险，使我们更好地了解它们的安置方式，以及这可能如何影响泥石流流出距离，以及这些潜在破坏性沉积物对近表层沉积物的影响。拟议的研究分为两个阶段：1）“质量消耗在年轻活动裂谷系统演化中的作用：来自科林斯湾的例子”。该研究线涉及对分裂岩心的高分辨率线扫描图像的解释，以了解在质量浪费期间发生的变形的沉积学和结构样式。在科林斯湾钻探期间回收的岩芯保存了厚（米级）碎屑岩和滑塌沉积物，并有不同类型的运输和侵位证据。通过解释这些分裂岩心的线扫描图像，我们可以确定每个块体运动存款的关键特征，如脆性和塑性软沉积物变形的风格，同沉积盆地内侵蚀（撕裂碎屑）和改造预先存在的沉积物的证据，以及在块体运动过程中液化和均质化的证据，以及质量流/碎屑和底层沉积物内的基底剪切。结果将被解释的主要侵位方式，这些群众运动存款（如滑塌与泥石流）和他们的影响，沉积的同裂谷沉积。2）“宏观和微观尺度的证据，群众运动侵位机制在科林斯湾”。项目的这一部分侧重于对滑塌和碎屑进行详细的微观分析（使用Micro-CT扫描图像和薄片分析），并将对这些块状运动矿床在剥离、运输和就位过程中发生的就位机制和过程（如韧性剪切、脆性破坏、液化、水力压裂）提供重要见解。重点将是调查在质量运输过程中的变形风格的变化，并将这些与占主导地位的侵位机制（如基底剪切，滑水）及其对底层沉积物的影响。这项研究的结果对了解不仅控制质量流就位的因素，而且控制这些矿床的流出距离及其对海底基础设施的影响的可能性具有意义（例如管道、电缆）。拟议的研究将使用多个数据集来产生（至少）两篇学术文章，在同行评审的期刊上发表。更多详情，请参阅附件“拟议研究的描述”。

This Moratorium Award proposal aims to provide a greater understanding of the emplacement mechanisms of mass failure deposits, in both macro- and micro-scale resolution, recovered within cores from Hole M0079A from IODP Expedition 381, "Corinth Active Rift Development". The project will aid in addressing one of the primary objectives of the Expedition, that of understanding surface processes in active rifts and the relative impacts of tectonics and climate on sediment flux. It will also contribute towards the secondary objective of improving our understanding of seismic, landslide and tsunami hazards within the Corinth Rift area. To achieve these goals it is crucial to understand previous mass failure events throughout the evolution of the rift basin for both syn-rift sediment infill and landslide frequency analysis in relation to regional geohazards. Furthermore, this study will contribute to evaluating the potential risks of subaqueous mass flows on seabed infrastructure (e.g. cables, pipelines, seabed installations) by increasing our understanding of their mode of emplacement and how this might affect debris flow run-out distances, and the impacts of these potentially destructive deposits upon near-surface sediments. There are two phases to the proposed research:1) "The role of mass wasting in the evolution of a young active rift system: examples from the Gulf of Corinth". This research line involves the interpretation of high-resolution line scan images of split cores to understand the sedimentological and structural styles of deformation occurring during mass wasting. Cores recovered during drilling in the Gulf of Corinth preserved thick (metre-scale) debrite and slump deposits, with evidence of different styles of transport and emplacement. By interpreting these line scan images of split cores, we can identify key features of each mass movement deposit, such as styles of brittle and plastic soft-sediment deformation, evidence of syn-sedimentary intra-basinal erosion (rip-up clasts) and reworking of pre-existing sediments, and evidence of liquefaction and homogenisation during mass movement, as well as basal shearing within both the mass flow/debrite and underlying sediments. The results will be interpreted in terms of the dominant emplacement styles of these mass movement deposits (e.g. slumping vs debris flow) and their implications for the deposition of the syn-rift sediments.2) "Macro- and Micro-scale evidence of mass movement emplacement mechanisms in the Gulf of Corinth". This part of the project focuses on the detailed micro-scale analysis of the slumps and debrites (using Micro-CT scan images and thin section analysis) and will provide critical insights into the emplacement mechanisms and processes (e.g. ductile shearing, brittle failure, liquefaction, hydrofracturing) occurring during the detachment, transport and emplacement of these mass movement deposits. The focus will be on investigating the changes in the style of deformation during mass transport and relating these to the dominant emplacement mechanism (e.g. basal shearing, hydroplaning) and their impacts upon the underlying sediments. The results of this study have implications for understanding the factors controlling not only mass flow emplacement, but also the run out distances of these deposits and their potential for impacting upon seafloor infrastructure (e.g. pipelines, cables).The proposed research would use multiple datasets to produce (a minimum of) two academic articles for publication in peer-reviewed journals.For further details, please see the attachment "Description of Proposed Research".